A tetrasaccharide flavonoid glycoside antioxidant, its preparation method and application

Abstract

The present invention discloses a tetrasaccharide flavonoid glycoside antioxidant and its preparation method and application, belonging to the technical field of natural medicines. The specific preparation method is as follows: extraction, extraction, rough separation by silica gel chromatography column, open column chromatography separation by microporous resin, separation by reversed-phase medium-pressure chromatography column, and purification by reversed-phase preparative column. The tetrasaccharide flavonoid glycoside antioxidant prepared by the present invention has obvious antioxidant activity, can be used for the preparation of antioxidant drugs, and has good economic benefits and application prospects.

Description

Technical Field

[0001] The present invention relates to the technical field of natural medicines, and particularly relates to a tetrasaccharide flavonoid glycoside antioxidant and its preparation method and application. Background Art

[0002] Lepidium latifolium L., a plant of the genus Lepidium in the family Brassicaceae, is also known as Dala, Lalagen, and Zhilizao. Recorded in "Medicinal Plants in Desert Areas of China", it has the effects of clearing heat and dampness, and treating bacillary dysentery and enteritis. As a plant with both medicinal and edible uses, Lepidium latifolium grows on the edges of fields, ridges, ditches, and river valleys, and is distributed in Gansu, Qinghai, Ningxia and other places. It is widely distributed and rich in resources, and has certain development and utilization value. Through literature research, it is found that there is less research on the chemical constituents of Lepidium latifolium, and further in-depth research is needed to clarify the material basis of the medicinal efficacy of Lepidium latifolium.

[0003] Oxidative Stress (OS): It refers to a state of imbalance between oxidation and antioxidant action in the body, tending to oxidize, resulting in neutrophil inflammatory infiltration, increased protease secretion, and the production of a large number of oxidative intermediate products. Oxidative stress is a negative effect produced by free radicals in the body and is considered an important factor leading to aging and some diseases. Among them, in the FRAP method, in a solution with low pH, Fe 3+ -TPTZ (Fe 3+ -tripyridyltriazine) can be reduced by antioxidants to colored (Prussian blue) Fe 2+ -TPTZ, which has the maximum absorbance at a wavelength of 593 nm. The higher the absorbance, the stronger the reducing ability. This method is convenient, simple, easy to operate, and has good repeatability. This method is widely used in the in vitro antioxidant capacity test and antioxidant screening. Summary of the Invention

[0004] The purpose of the present invention is to provide a tetrasaccharide flavonoid glycoside antioxidant and its preparation method and application to solve the problems existing in the prior art. The tetrasaccharide flavonoid glycoside substance extracted and separated from Lepidium latifolium in the present invention has good in vitro antioxidant activity.

[0005] To achieve the above purpose, the present invention provides the following solutions:

[0006] One of the technical solutions of the present invention: A tetrasaccharide flavonoid glycoside antioxidant, and the molecular formula of the tetrasaccharide flavonoid glycoside antioxidant is C 49 H 58 O 28, named (kaempferol-3-O-β-D-glucopyranosyl(1→2)-[(2-O-feruloyl)-β-D-glucopyranosyl](1→4)-β-D-glucopyranosyl-7-O-α-L-rhamnoside), with the structural formula as follows:

[0007]

[0008] The second technical solution of the present invention: A preparation method of the above-mentioned tetrasaccharide flavonoid glycoside antioxidant, comprising the following steps:

[0009] (1) Add Lepidium latifolium to an ethanol solution, heat under reflux for extraction, recover under reduced pressure to obtain a crude extract, extract the crude extract with n-butanol, and recover under reduced pressure to obtain an extraction sample;

[0010] (2) Coarse separation by silica gel column chromatography: Add the extraction sample to a silica gel column, elute with a dichloromethane-methanol mixed solvent with a volume ratio of 15:1 to 1:1 in a gradient manner, collect the eluate eluted with a dichloromethane-methanol mixed solvent with a volume ratio of 1:1 to obtain fraction Fr.5;

[0011] (3) Micro-porous resin open column chromatography separation: Add fraction Fr.5 to a micro-porous resin open column chromatography, perform gradient elution with a methanol / water system, collect the eluate with a methanol volume concentration of 50% to obtain fraction Fr.5-6;

[0012] (4) Reverse-phase medium-pressure column chromatography separation: Add fraction Fr.5-6 to a reverse-phase high-pressure column, collect the chromatographic peak fractions at 25 - 30 min to obtain fraction Fr.5-6-1;

[0013] (5) Reverse-phase preparative column purification: Add fraction Fr.5-6-1 to a reverse-phase preparative column, collect the chromatographic peak fractions at 21 - 25 min to obtain the above-mentioned tetrasaccharide flavonoid glycoside antioxidant.

[0014] Further, in step (1), the mass / volume ratio of the Lepidium latifolium to the ethanol solution is 1 kg:5 - 50 L; the volume fraction of the ethanol solution is 95%; the temperature of the heating extraction is 70 °C, the number of extraction times is 2 - 4 times, and the extraction time for each time is 2 - 4 h.

[0015] Further, in step (1), the number of extraction times is 2 - 4 times.

[0016] Further, in step (3), the volume concentration of methanol in the methanol / water system increases by 10% successively, and each gradient elutes for 2 - 3 column volumes.

[0017] Further, in step (4), the working parameters for separation by the reversed-phase medium-pressure chromatography column are as follows: column length 250 mm, diameter 20 mm, stationary phase is Dubhe C18 with a particle size of 5 μm, mobile phase A is 0.2% formic acid - water, mobile phase B is acetonitrile. From 0 to 40 min, it is eluted with 88% of mobile phase A and 12% of mobile phase B. The injection volume is 0.2 mL, and the flow rate is 19 mL / min.

[0018] Further, in step (5), the working parameters for purification by the reversed-phase preparative column are as follows: column length 250 mm, diameter 10 mm, stationary phase is epoxy tetrazole with a particle size of 5 μm, mobile phase A is 0.2% formic acid - aqueous solution, mobile phase B is acetonitrile. From 0 to 60 min, it is eluted with 96% of mobile phase A and 4% of mobile phase B. The injection volume is 0.2 mL, and the flow rate is 5.0 mL / min.

[0019] The third technical solution of the present invention: An application of the above-mentioned tetrasaccharide flavonoid glycoside antioxidant in the preparation of antioxidant drugs.

[0020] The present invention discloses the following technical effects:

[0021] Using the preparation method of the present invention, a new tetrasaccharide flavonoid glycoside compound with relatively high purity can be extracted. This compound has good antioxidant activity, and its antioxidant ability is superior to that of vitamin C and quercetin, and it can be used for the development and preparation of new antioxidant-related drugs. Description of the Drawings

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0023] Figure 1 It is the ultraviolet spectrum of the compound prepared in Example 1 of the present invention;

[0024] Figure 2 It is of the compound prepared in Example 1 of the present invention 1 1H-NMR spectrum;

[0025] Figure 3 It is of the compound prepared in Example 1 of the present invention 13 13C-NMR spectrum;

[0026] Figure 4 It is of the compound prepared in Example 1 of the present invention 1 1H- 1 1H COSY spectrum;

[0027] Figure 5 The HSQC spectrum of the compound prepared in Example 1 of the present invention;

[0028] Figure 6 The homonuclear TOCSY spectrum of the compound prepared in Example 1 of the present invention;

[0029] Figure 7 The HMBC spectrum of the compound prepared in Example 1 of the present invention;

[0030] Figure 8 The ROESY spectrum of the compound prepared in Example 1 of the present invention;

[0031] Figure 9 The comparison chart for measuring the antioxidant capacity of Example 1 of the present invention. Detailed implementation manners

[0032] Now, various exemplary implementation manners of the present invention will be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, characteristics, and implementation schemes of the present invention.

[0033] It should be understood that the terms described in the present invention are only for describing specific implementation manners and are not used to limit the present invention. Additionally, for the numerical ranges in the present invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each intermediate value within any stated value or stated range, as well as each smaller range between any other stated value or intermediate value within the stated range, is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded from the range.

[0034] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention pertains. Although the present invention only describes preferred methods and materials, any methods and materials similar or equivalent to those described herein can also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and materials related to the documents. In case of conflict with any incorporated document, the content of this specification shall prevail.

[0035] Without departing from the scope or spirit of the present invention, various improvements and changes can be made to the specific implementation manners of the specification of the present invention, which are obvious to those skilled in the art. Other implementation manners obtained from the specification of the present invention are obvious to those skilled in the art. The specification and examples of this application are only exemplary.

[0036] Regarding the use of "comprising", "including", "having", "containing", etc. herein, they are all open-ended terms, meaning including but not limited to.

[0037] Example 1

[0038] A preparation method of a tetrasaccharide flavonoid antioxidant:

[0039] (1) Extraction: Air-dry 10 kg of the whole herb of Lepidium latifolium L., coarsely crush it and then sieve it through a 40-mesh sieve to obtain the powder of the whole herb of Lepidium latifolium L. Then mix the powder of the whole herb of Lepidium latifolium L. with an ethanol solution with a volume fraction of 95% at a mass / volume ratio of 1 kg:10 L, extract it 3 times at 70 °C for 2 h each time, combine the extracts, and recover under reduced pressure (the vacuum degree for reduced pressure recovery is 0.07 - 0.09 MPa, and the temperature is 50 - 60 °C) to obtain a crude extract.

[0040] (2) Extraction: Dilute 800 g of the crude extract with water to 4 L, then extract it 4 times with an equal volume of n-butanol, and recover under reduced pressure (the vacuum degree for reduced pressure recovery is 0.07 - 0.09 MPa, and the temperature is 50 - 60 °C) to obtain an extraction sample.

[0041] (3) Coarse separation by silica gel column chromatography: After mixing the extraction sample with silica gel (200 - 300 mesh), separate it through a normal-phase silica gel column, and perform gradient elution successively with dichloromethane-methanol mixed solvents with volume ratios of 15:1, 10:1, 8:1, 5:1, and 1:1. Collect the eluate eluted with the dichloromethane-methanol mixed solvent with a volume ratio of 1:1, and recover under reduced pressure (the vacuum degree for reduced pressure recovery is 0.07 - 0.09 MPa, and the temperature is 50 - 60 °C) to obtain fraction Fr.5.

[0042] (4) Separation by open column chromatography of microporous resin: Dissolve fraction Fr.5 in water, filter it through a membrane, and load it onto the column by the wet method. Separate it by open column chromatography of microporous resin (the stationary phase is MCI microporous resin, the mobile phase A is water, and the mobile phase B is methanol); use the methanol / water system to linearly increase the methanol concentration from 0, 10%, 20%, 30%..., 100% for gradient elution. Elute for 2 column volumes at each gradient, and obtain 10 elution fractions separately, and recover under reduced pressure (the vacuum degree for reduced pressure recovery is 0.07 - 0.09 MPa, and the temperature is 50 - 60 °C), denoted as Fr.5-1 to Fr.5-10.

[0043] (5) Separation by reverse-phase medium-pressure column chromatography: Add fraction Fr.5-6 to a reverse-phase high-pressure column, detect (the detector is an ultraviolet detector, and the detection wavelength is 254 nm), collect the corresponding chromatographic peak fractions in the preparative chromatogram, and recover under reduced pressure (the vacuum degree for reduced pressure recovery is 0.07 - 0.09 MPa, and the temperature is 50 - 60 °C) to obtain fraction Fr.5-6-1.

[0044] The working parameters for separation by the reversed-phase medium-pressure chromatography column are as follows: column length 250 mm, diameter 20 mm, stationary phase is Dubhe C18 with a particle size of 5 μm, mobile phase A is 0.2% formic acid - water, mobile phase B is acetonitrile. Elution is carried out at 88% mobile phase A and 12% mobile phase B from 0 to 40 min, the injection volume is 0.2 mL, and the flow rate is 19 mL / min.

[0045] (6) Purification by reversed-phase preparative column: Component Fr.5 - 6 - 1 was added to the reversed-phase preparative column, and the corresponding chromatographic peak fractions in the preparative chromatogram were detected (the detector is an ultraviolet detector, and the detection wavelength is 254 nm) and collected, and then recovered under reduced pressure (the vacuum degree for reduced-pressure recovery is 0.07 - 0.09 MPa, and the temperature is 50 - 60 °C) to obtain component Fr.5 - 6 - 1 - 2 (a tetrasaccharide flavonoid compound with a purity greater than 95%, that is, a tetrasaccharide flavonoid antioxidant).

[0046] The working parameters for purification by the reversed-phase preparative column are as follows: column length 250 mm, diameter 10 mm, stationary phase is epoxy tetrazole with a particle size of 5 μm, mobile phase A is 0.2% formic acid - aqueous solution, mobile phase B is acetonitrile. Elution is carried out at 96% mobile phase A and 4% mobile phase B from 0 to 60 min, the injection volume is 0.2 mL, and the flow rate is 5.0 mL / min.

[0047] Structure identification: Take the compound prepared in this example and use spectroscopic techniques: ultraviolet, infrared, mass spectrometry, nuclear magnetic resonance (UV, IR, MS, 1 H-NMR, 13 C-NMR, 2D-NMR) to identify its structure and molecular formula.

[0048] The analysis process and spectral data of this compound are as follows:

[0049] The compound is a pale yellow amorphous powder. ESI-MS shows that the molecular ion peak is m / z: 1093.55 [M - H] - , combined with the NMR data, the molecular formula is determined to be C 49 H 58 O 28 , and its degree of unsaturation is 21. Its ultraviolet spectrum (214 nm, 331 nm) indicates that this compound is a flavonoid compound. The 13 C-NMR data shows that the anomeric carbon signals at δ104.49, 99.92, 98.74, 97.39, the methyl carbon signal at δ18.12, and the other 19 characteristic carbon signals show the presence of three pyranosyl units and one rhamnosyl unit. In addition, 13The carbon signals at 157.62 (C-2), 134.93 (C-3), 179.35 (C-4), 162.55 (C-5), 100.55 (C-6), 163.28 (C-7), 94.90 (C-8), 157.87 (C-9), 107.51 (C-10), 122.89 (C-1'), 116.17 (C-3',5'), 161.52 (C-4'), 132.20 (C-2',6') in the 3 13C NMR spectrum and the carbon signals at 127.20 (feruloyl-C-1), 110.64 (feruloyl-C-2), 148.80 (feruloyl-C-3), 150.13 (feruloyl-C-4), 116.05 (feruloyl-C-5), 123.35 (feruloyl-C-6), 146.31 (feruloyl-C-7), 115.58 (feruloyl-C-8), 168.26 (feruloyl-C-9), 56.02 (feruloyl-OCH 1 ) show 14 carbon signals of 3-O-glycosylated-7-O-glycosylated kaempferol and 10 carbon signals of the feruloyl moiety. Therefore, this compound is a tetrasaccharide kaempferol containing a feruloyl group. 1 1H NMR indicates that there are three sets of aromatic protons in the compound. One set corresponds to signals at δ 6.45 (1H, d, J = 2.0 Hz, H-8), 6.33 (1H, d, J = 2.2 Hz, H-6), representing a tetrasubstituted aromatic ring with two meta-coupled protons, attributed to the proton signals of the A ring of kaempferol; the second set are the para-substituted benzene proton signals at δ 7.89 (2H, d, J = 8.8 Hz, H-2',6') and 6.89 (2H, d, J = 8.7 Hz, H-3',5'), attributed to the proton signals of the B ring of kaempferol; the third set of aromatic proton signals are 6.65 (1H, br s, feruloyl-H-2), 6.56 (1H, br d, J = 8.4 Hz, feruloyl-H-6), 6.46 (1H, d, J = 8.0 Hz, feruloyl-H-5), and the third set of protons are coupled with δ 7.33 (1H, d, J = 15.8 Hz, feruloyl-H-7), 6.11 (1H, d, J = 15.8 Hz, feruloyl-H-8), 3.68 (3H, s, feruloyl-OCH 3 ) and belong to the feruloyl proton signals. Among them, based on the large coupling constant (J = 15.8 Hz) of δ 7.33 and δ 6.11, the geometric structure of the double bond is speculated to be trans. According to the anomeric proton δ 6.08 (1H, d, J = 7.4 Hz, g1c-H-1), 5.23 (1H, d, J = 7.9 Hz, g1c2 -H-1) and δ4.47 (1H, d, J = 7.8 Hz, g1c 3 The large coupling constants of -H-1) determine that the three pyranose moieties are in the β-configuration.

[0050] By analyzing 1 H- 1 H COSY, HSQC and homonuclear TOCSY spectra enable the assignment of the glycoside proton system. The HMBC spectrum confirmed the connectivity of the glycosyl, kaempferol and feruloyl moieties, where δ6.08 (1H, d, J = 7.4 Hz, g1c-H-1) correlates with 134.93 (C-3), 5.23 (1H, d, J = 7.9 Hz, g1c 2 -H-1) correlates with 82.13 (g1c-C-2), δ4.47 (1H, d, J = 7.8 Hz, g1c 3 -H-1) and 79.53 (g1c 2 -C-4) correlate, 5.54 (1H, br s, rha-H-1) and 163.28 (C-7) correlate, 4.98 - 4.95 (1H, dd, J = 9.5, 7.9 Hz, g1c 2 -H-2) and 168.26 (feruloyl-C-9) correlate. Based on all these results, the structure of the compound was established as kaempferol-3-O-β-D-glucopyranosyl(1→2)-[(2-O-feru-loyl)-β-D-glucopyranosyl](1→4)-β-D-glucopyranosyl-7-O-α-L-rhamnopyranoside, and named lepidiumoside, with the structural formula as follows:

[0051]

[0052] The UV spectrum of the compound is shown in Figure 1 , 1 The 1H-NMR spectrum is shown in Figure 2 , 13 The 13C-NMR spectrum is shown in Figure 3 , 1 H- 1 H COSY spectrum is shown in Figure 4 , the HSQC spectrum is shown in Figure 5 , the homonuclear TOCSY spectrum is shown in Figure 6 , the HMBC spectrum is shown in Figure 7 , the ROESY spectrum is shown inFigure 8 .

[0053] 13 The C-NMR and 1 the H-NMR data attribution is shown in Table 1.

[0054] Table 1 NMR data table

[0055]

[0056]

[0057] 1 1H NMR (600 MHz) and 13 13C NMR (150 MHz) measured in methanol-d 4 (measured with deuterated methanol).

[0058] Effect Example 1

[0059] Antioxidant activity experiment

[0060] The total antioxidant capacity of the sample was measured using a total antioxidant capacity (T-AOC) assay kit.

[0061] The test procedure is as follows:

[0062] (1) Prepare the FeSO 4 -7H 2 O standard solution: Weigh 27.8 mg of FeSO 4 -7H 2 O standard (provided by the total antioxidant capacity (T-AOC) assay kit), dissolve it with 1 mL of 50 vol.% methanol to prepare a solution with a concentration of 100 mM, and dilute it to standard solutions with concentrations of 0.15, 0.3, 0.6, 0.9, 1.2, and 1.5 mM respectively.

[0063] (2) Prepare the positive control: Weigh 3.6 mg of vitamin C precisely, prepare a vitamin C solution with a concentration of 3.6 mg / mL, add 50 vol.% methanol and dilute it to 0.2 mg / mL. Weigh 6.1 mg of quercetin precisely, prepare a quercetin solution with a concentration of 6.1 mg / mL, add 50 vol.% methanol and dilute it to 0.2 mg / mL; Prepare the sample solution: Weigh 2.2 mg of Fr.5-6-1-2 lepidiumoside precisely, prepare a lepidiumoside solution with a concentration of 2.2 mg / mL, add 50% methanol and dilute it to 0.2 mg / mL.

[0064] (3) In a 96-well plate, set blank wells, standard wells, and measurement wells. Add 5 μL of 50 vol.% methanol and 180 μL of FRAP working solution to the blank wells. Add standard solution of different concentrations of FeSO 4 -7H 2 O to the standard wells. Add 5 μL of the sample solution to be measured and 180 μL of FRAP working solution to the measurement wells. Mix well, incubate at 37 °C for 3 - 5 min, measure the absorbance at 593 nm, and repeat three times for each sample; read the OD values of each well with an enzyme-linked immunosorbent assay (ELISA) reader.

[0065] (4) Standard curve: After subtracting the absorbance value of the blank well from each well, use the absorbance value of the standard as the abscissa and the corresponding standard concentration of each absorbance value as the ordinate to make a standard curve, and obtain the curve formula using EXCEL.

[0066] (5) Calculation: Substitute the absorbance value measured in the sample measurement tube (subtracting the blank absorbance value) into the standard curve formula, and express the result in terms of the concentration of the FeSO 4 -7H 2 O standard solution, that is, mM. The results are shown in Figure 9 .

[0067] As can be seen from Figure 9 , the antioxidant performance of the tetrasaccharide flavonoid glycoside antioxidant prepared in the present invention (0.33 ± 0.02 mM) is significantly better than that of quercetin (0.22 ± 0.06 mM) and (0.06 ± 0.05 mM).

[0068] The above-described embodiments are only descriptions of the preferred embodiments of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A tetrasaccharide flavonoid glycoside antioxidant, characterized in that, The molecular formula of the tetrasaccharide flavonoid antioxidant is C 49 H 58 O 28 , and the structural formula is:

2. A method for preparing the tetrasaccharide flavonoid glycoside antioxidant according to claim 1, characterized in that, comprising the following steps: (1) Add Lepidium latifolium to an ethanol solution, heat under reflux for extraction, recover under reduced pressure to obtain a crude extract, extract the crude extract with n-butanol, and recover under reduced pressure to obtain an extraction sample; (2) Coarse separation by silica gel chromatography column: Add the extraction sample to a silica gel chromatography column, elute with a dichloromethane-methanol mixed solvent with a volume ratio of 15:1 to 1:1 in a gradient manner, and collect the eluate eluted with a dichloromethane-methanol mixed solvent with a volume ratio of 1:1 to obtain fraction Fr.5; (3) Microporous resin open column chromatography separation: Add fraction Fr.5 to a microporous resin open column chromatography, elute with a methanol / water system in a gradient manner, and collect the eluate with a methanol volume concentration of 50% to obtain fraction Fr.5-6; (4) Reversed-phase medium-pressure chromatography column separation: Add fraction Fr.5-6 to a reversed-phase high-pressure chromatography column, collect the chromatographic peak fractions at 25 - 30 min to obtain fraction Fr.5-6-1; (5) Reversed-phase preparative column purification: Add fraction Fr.5-6-1 to a reversed-phase preparative column, collect the chromatographic peak fractions at 21 - 25 min to obtain the tetrasaccharide flavonoid glycoside antioxidant.

3. The method for preparing the tetrasaccharide flavonoid glycoside antioxidant according to claim 2, characterized in that, in step (1), the mass / volume ratio of the Lepidium latifolium to the ethanol solution is 1 kg:5 - 50 L; the volume fraction of the ethanol solution is 95%; the temperature of the heating extraction is 70 °C, the number of extraction times is 2 - 4 times, and the extraction time for each time is 2 - 4 h.

4. The method for preparing the tetrasaccharide flavonoid glycoside antioxidant according to claim 2, characterized in that, in step (1), the number of extraction times is 2 - 4 times.

5. The method for preparing the tetrasaccharide flavonoid glycoside antioxidant according to claim 2, characterized in that, in step (3), the volume concentration of methanol in the methanol / water system increases by 10% successively.

6. The method for preparing the tetrasaccharide flavonoid glycoside antioxidant according to claim 2, characterized in that, in step (4), the working parameters of the reversed-phase medium-pressure chromatography column separation are: column length 250 mm, diameter 20 mm, stationary phase is 5 μm Dubhe C18, mobile phase A is 0.2% formic acid-water, mobile phase B is acetonitrile, elute according to the elution time of 0 - 40 min with 88% mobile phase A and 12% mobile phase B, injection volume is 0.2 mL, and flow rate is 19 mL / min.

7. The method for preparing the tetrasaccharide flavonoid glycoside antioxidant according to claim 2, characterized in that, in step (5), the working parameters of the reversed-phase preparative column purification are: column length 250 mm, diameter 10 mm, stationary phase is 5 μm epoxy tetrazole, mobile phase A is 0.2% formic acid-aqueous solution, mobile phase B is acetonitrile, elute according to 0 - 60 min with 96% mobile phase A and 4% mobile phase B, injection volume is 0.2 mL, and flow rate is 5.0 mL / min.

8. Use of the tetrasaccharide flavonoid glycoside antioxidant according to claim 1 in the preparation of antioxidant drugs.

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